The automatic processing of spoken language encompasses a wide variety of technologies and applications. Automatic speech-to-text conversion enables automatic transcription of speeches, conversations and audio broadcasts. Automatic speech recognition, or voice recognition, enables users to use their mobile phones, access databases and control home appliances using voice commands. Speaker recognition technologies are used in authentication applications and surveillance systems.
Speech processing is closely related to Natural Language Processing (NLP), a group of technologies that interpret and process speech data using linguistic models.
Processing of speech, or spoken language, is covered extensively in the patent literature. For example, U.S. Pat. No. 5,946,656 describes a method for speech and speaker recognition using Hidden Markov models (HMM). U.S. Pat. No. 4,060,694 discloses a method for speech recognition adapted to a plurality of different speakers. The disclosures of these patents and of the patents and publications cited below are incorporated herein by reference.
Several speech processing applications utilize characteristics of the speaker. For example, U.S. Patent Application Publication 2002/0095295 describes a system that uses automatic speech recognition to provide dialogs with human speakers. The system automatically detects characteristics of the speaker, his speech, his environment, or the speech channel used to communicate with the speaker. U.S. Patent Application Publication 2004/0002994 describes a system and method for performing automated error correction of user input data via an analysis of the input data in accordance with a database of past user activities, such as phrases, topics, symbols and speech samples.
Other speech processing applications utilize the characteristics of the spoken language. For example, U.S. Pat. No. 6,526,382 describes a voice activated user interface having a semantic and syntactic structure adapted to the culture and conventions of spoken language. For example, U.S. Patent Application Publication 2003/0061030 presents a natural language processing apparatus, which executes morphological analysis. U.S. Patent Application Publication 2004/0193401 discloses linguistically-informed statistical models of constituent structure for ordering in sentence realization for a natural language generation system. U.S. Pat. No. 5,999,896 describes a method and system for identifying and resolving commonly confused words in a natural language parser. U.S. Pat. No. 5,926,784 describes a method and system for natural language parsing.